Key cutting machine



April 29, 1969 w. H. ALLEN 3,440,906

KEY CUTTING MACHINE Filed Oct. 27, 1966 Sheet of 5 INVENTOR; WILLIAM H. ALLEN BY 3 1M 30 1 ATT'YS W. H. ALLEN KEY CUTTING MACHINE April 29, 1969 R 5 m S f N o E T V T. llllllll ll N m Sheet WILLIAM H. ALL E N Mm 0%),

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Filed Oct.

April 29, 1969 w. H. ALLEN KEY CUTTING MACHINE Sheet 5 M5 Filed Oct. 27, 1966 INVENTOR:

WILLIAM H. ALLEN I 1 gi mv A T T Y s April 29, 1969 w. H. ALLEN 3,440,906

KEY CUTT 1 N6 MACHINE Filed Oct. 27, 1966 Sheet 4 of 5 FIG. 5

INVENTOR: WILLIAM H. ALLEN April 1969 w. H. ALLEN 3,440,906

KEY CUTT ING MACHINE Filed Oct. 27, 1966 Sheet 5 of 5 2 83 2lc 83b 9eq g. a v

FIGS

INVEN'IOR. WILLIAM H. ALLEN fiawlm qtlm aalm (W),

ATT'YS United States Patent 3,440,906 KEY CUTTING MACHINE William H. Allen, 400 Hill, Hannibal, M0.

Filed Oct. 27, 1966, Ser. No. 590,056 Int. Cl. B21k 13/00; 1323c 1/16, 1/18 US. Cl. 76-110 11 Claims ABSTRACT OF THE DISCLOSURE The common cylinder-type lock comprises generally a removable cylinder or plug having a keyhole, and it is received in a corresponding hollow within the lock housing. Rotation of the cylinder within the housing causes the lock plunger to protrude from the housing in a locked position. Counter rotation will retract the plunger. The cylinder is fitted with a series of holes or barrels extending radially through the exterior surface of the cylinder and forming a straight line with its axis. These barrels, in turn, are fitted with pins of varying lengths, none of which extend beyond the exterior surface of the cylinder or plug absent a key in the keyhole. The lock housing is further provided with corresponding pins which are springloaded to fit into the barrels in the cylinder to bear against the cylinder pins. The lock is in a locked position when the housing pins extend into the cylinder barrels to prevent its rotation or when an improper key is inserted into the keyhole forcing the cylinder pins into housing barrels and thereby preventing rotation of the cylinder. When the bit portion of a key is inserted into the cylinder through the keyhole and the notches or wards on the key bit are the proper depth for forcing their associated cylinder pins to form a smooth surface with the exterior of the cylinder, the cylinder may be rotated.

Key cutting machines for duplicating keys have long been known. Methods are also known for cutting original or first keys when there is no sample from which to duplicate. Such methods and machines are common for locks of either the pin tumbler or the wafer or disc tumbler type. According to one such method, the cylinder and its tumblers (either pin or disc) are removed from the lock housing, and a first blank key is inserted in the keyhole of the cylinder thereby forcing the tumblers outwardly from the cylinder a distance equal to the depth of the wards in a key adapted to fit the lock. Wards are then cut in a second key having a depth equal to the protrusion of the tumblers beyond the cylinder surface when a blank key is inserted. The distance between wards, longitudinal of the key bit, may be obtained by reference to the distance between the protruding tumblers. When this newly cut key is inserted into the keyhole, since the depth of the notches or wards in it are exactly equal to the the protrusion of the tumblers beyond the cylinder surface when a blank key is inserted, the tumblers will line up with the cylinder surface when the new key is inserted.

Machines designed to out such first keys, that is machines which do not simply duplicate an existing key, have in the past been very bulky and cumbersome machines, not easily transported, as is desirable. In addition to being a first key machine, the instant invention allows an operator to cut a key from coding information supplied by the manufacturer in accordance with his specifications thereby obviating the need for either an original key or a lock cylinder and tumblers. Heretofore, it was 3,440,906 Patented Apr. 29, 1969 "ice believed that gathering such information was impractical, but I have arrived at a convenient and economical solution to this problem. This allows an operator to cut a key, for example, from the coding information stamped on the levers of a lever type lock wherein the rotating cylinder cooperates with a series of levers to open the lock and wherein there are no protruding cylinder tumblers for establishing a reference for cutting, the coding information being on the levers. Further provision is made on the instant machine for duplicating keys as a convenience.

In addition to the above disadvantages of prior art machines, they have not made provision for milling the flat bottom portions of the wards to specifications. The length of the flat, which extends along the length of the key, varies for different manufacturers.

One object of the present invention is to provide a novel key cutting machine for cutting original keys from the lock cylinder and tumblers.

Another object of the present invention is to provide a key cutting machine capable of milling the flat of the wards of a key to specification with only a single milling cutter.

A still further object of the present invention is to provide a key cutting machine wherein first keys may be cut from the coding information on the lock according to the manufacturers specification.

An even further object of the present invention is to provide key cutting machine which facilitates the implementation of master key systems.

Other objects and advantages of the present invention will be obvious to those skilled in the art from the following detailed description accompanied by the attached drawing in which:

FIG. 1 is a partially cutaway top view of a machine according to the present invention;

FIG. 2 is a rear elevational view of the machine of FIG. 1;

FIG. 3 is a partially cutaway side elevational view of the machine of FIG. 1 in its normal position;

FIG. 4 is the same view as FIG. 3 with the machine in a key-cutting position;

FIG. 5 is a view of the underside of the frame of the machine of FIG. 1 showing the operating lever controls;

FIG. 6 is a sectional side elevational view of the machine of FIG. 1 showing the mechanism for making a set up when used either as a code or an original key machine;

FIG. 7 shows a code plug for use with the apparatus of FIG. 1 as a code machine; and

FIG. 8 indicates an alternate use of the machine of FIG. 1 wherein the mill cutter is replaced by a slotter wheel for cuttingwards in fiat steel keys.

In the illustrated embodiment of the present invention, identical reference numerals will be used on the various views to indicate like parts of the machine. Referring to the drawing, and particularly to FIGS. 1 and 2, the key cutting machine is mounted on a hollow base 10 which has a horizontal upper surface for mounting the cutting mechanism. The base 10 also serves as a housing for an electrical motor (shown in phantom as 10a in FIG. 2) which has a drive shaft 12 extending out of the side of frame 10 for driving an endless belt 14. The endless drive belt 14 is fitted around a driven pulley 16 mounted on a driven shaft 18 on the other end of which is mounted the milling cutter wheel 20 by means of a nut 20a threaded on the shaft 18 thereby forcing the cutter wheel 20 against a flange 20b fixed on the driven shaft 18.

Extending out from the front side of the base 10 for convenient accessibility are: a cutting lever 21a which when depressed will move the key desired to be cut into 3 the cutter wheel 20; a set up crank handle 21b which performs the set up when rotated; and a fiat-control lever 210 which when depressed will move cutter wheel 20 horizontally to mill a fiat in the key being cut. The operation of these levers and the crank handle will be made clear below.

Fixed below the driven shaft 18 and parallel to it is a shaft 21 mounted at either end to the base in a manner described in more detail below. A key-bearing carriage 22 is rotatably mounted on the shaft 21 by means of cylinder bearings 22a and 22b. On top of the key-bearing carriage 22 is a table, indicated generally at 24 on which the key to be cut is fastened with the side in which the wards are to be cut facing the cutter wheel 20. A ridge, as at 26, is provided on .the table 24 for preventing a lateral movement of the key being cut. The key-bearing carriage 22 is further provided with a set of clamps designated as 28 and 30 (FIG. 1). Wing nuts 32 and 34 are threaded on to bolts 36 and 38 extending certically from the table 24 through the respective clamps 28 and 30 thereby forming a left and right vise (when viewed from the front) for clamping keys while duplicating. In the duplicating operation, the original key is clamped in the right vise 30 and the key to be cut is clamped in the left vise 28. A housing 38 for the cutter wheel shaft 18 is provided with a fixed finger 40 which extends horizontally toward the key-bearing carriage 22 in the same spacial relationship as does the cutter wheel 20.

The key-bearing carriage 22 is adapted to move axially along the shaft 21 and also, as mentioned, to rotate about the shaft 21. The duplication is accomplished by simply engaging the finger 40 with the profile of the wards of the original key clamped in the right vise, and the duplicate key will be cut to the same profile by the cutter Wheel 20. This is approximately the same process as is used in conventional duplicating machines and forms no substantial part of the present invention.

The key-bearing carriage 22, as mentioned, is rotatably mounted on the shaft 21 by means of the two cylinder bearings connected to the table portion 24. Integral with the key-bearing carriage 22, but extending rearwardly of the shaft 21 is a member 42 which defines a receptacle for the cylinder lock, as seen generally at 42a and described in more detail below.

A leg member 44 is also rotatably mounted on shaft 21 by annular bearings 48 and 50 journaled on shaft 21. It will be noted that the annular bearings 48 and 50 abut the cylinder bearing a of the key-bearing carriage 22 on either side thereof. By this structure, whenever the carriage 22 is moved axially of the shaft 21, the leg 44 and annular bearings 48 and 50 are also translated horizontally. Conversely, if the leg 44 is restrained against lateral motion, the key-bearing carriage 22 is prevented from moving axially along the shaft 21 although it may rotate about the shaft 21. The leg 44 and the key-bearing carriage 22 are independently rotatable about the shaft 21.

The rear end of the leg member 44, that is, the end away from the shaft 21, is provided with an elongated foot 46 transverse of the leg 44. The bottom surface of the foot 46 rests on the top of the frame 10. It will be noted here that when the foot 46 is pressed against the top surface of the frame 10, the key-bearing carriage 22 is restrained from axial movement of shaft 21. This serves an important function in the operation of the machine, as will be clear from subsequent description, and is sometimes referred to as a drift control feature.

A flat steel spring 50a is attached to the under side of the rearward member 42 of carriage 22, and bent to bear against the upper surface of the leg 44 to bias the carriage 22 in a clockwise rotation around the shift 21 (see FIG. 4) when the leg 44 is forced against the frame 10. Thus, some force must be applied by an operator to rotate carriage 22 counterclockwise about shaft 21 in order to move the key which is to be cut toward the cutter wheel 20. This facilitates insertion and removal of the key since in its normal position the carriage 22 is biased away from the cutter wheel 20.

As mentioned above, the member 42 of carriage 22 is provided with a receptacle for the lock cylinder and tumblers, as best seen in FIGS. 1 and 4. The receptacle, generally designated as 42a defines a cylindrical hollow 54 with its axis parallel to the shaft 21. The receptacle 42a further comprises a vertically moveable platform 56 disposed longitudinally along the bottom of the hollow 54.

The lock cylinder and tumblers for which a key is desired are inserted into the receptacle 42a and held in place by forcing the platform 56 against the lower surface of the inserted cylinder. The platform 56 is raised and lowered by rotating a handle 57 threaded into the top of the member -42 and interconnected by a lever (not shown) with an extension of the platform 56 depending below the hollow 54. This forces the lock cylinder up against inwardly depending portions 59 of the hollow 54 as seen in FIG. 4. This forms a vise for the cylinder and accommodates lock cylinders of various diameter.

As seen in FIG. 4, when a plug is thus inserted as at 60 with a blank key in the keyhole 68 the pins protrude upwardly as at 69. A stop member 70 (FIG. 3) is attached to the side of frame 10 and is rotatable in a plane perpendicular to the axis of the hollow 54 to engage a key inserted in a plug in the receptacle 42a and prevent its movement beyond the edge of the frame 10. This stop 70 serves the function of lining up the lock cylinder and the key to be cut in the left hand vise 28. The key which is to be cut when clamped in the vise 28 in proper longitudinal orientation relative to cutter wheel 20, is similarly stopped from a leftward movement by a stop surface 71 which is an extension of the frame It] in a vertical plane. This will be made apparent below.

It will be noted that as the lock cylinder 60 is forced downward in receptacle 42a the member 42 is rotated in a counterclockwise direction about shaft 21, the key to be cut which is clamped in the left vise 28 on the keybearing carriage 22, will then be rotated into the cutting wheel 20. Clockwise rotation of the key-bearing carriage 22 is stopped by means of a nut and screw arrangement generally indicated at 72 (FIG. 3) bearing against the top of the frame 10. The shaft 21 is supported at one end by the lower portion of the housing for the cutter wheel shaft 18, and at the other end by the extension 71 of frame 10.

Also rotatably mounted on shaft 21 is a second carriage, hereinafter referred to as the finger carriage and generally designated as 75 in the drawing. The finger carriage 75 is rotatably mounted on the shaft 21 by means of first and second bearings 76 and 77; and the finger carriage 75 extends rearwardly behind the housing of the cutter wheel axis 18 slanting slightly upwardly from the shaft 21. The finger carriage 75 is provided with a micrometer 80 which is threaded through the finger carriage 75 and terminates in a set pin 82 which normally rests on a block 83 which is moveable in the vertical direction by rotation of the crank handle 21b as described below. The function of the pin 82 and its supporting block 83 is to limit counterclockwise rotation of the finger carriage 75 about shaft 21.

The carriage 75 has an extension 85 protruding leftward when viewed from the front in a direction generally above and parallel to the axis of the lock-cylinder-receiving hollow 54. The extension 85 has affixed to it a positioning finger 86 which takes the form of a hook looping above the carriage 75 and terminating in a tip which is directly over the axis of hollow 54. The function of the positioning finger 86 is to engage the pins protruding from a plug cylinder as shown in FIG. 4. It is noted that the carriage 75, though rotatable about the shaft 21 is restrained from any movement in an axial direction relative to the shaft 21. That is, the positioning finger 86 has a lateral position which is fixed relative to the cutter wheel 20; and the key-bearing carriage 22 supports both the lock cylinder and the key to be cut which move in unison relative to the finger 86 and the cutting wheel 20. Whatever longitudinal position the finger 86 takes relative to a blank key 68 inserted in the lock cylinder 60, the cutter Wheel 20 has the same position relative to a key inserted in the left vise 28 of the table 22.

Also a part of the carriage 75 is a member 90 (FIG. 2) extending generally below the extension 85 of the carriage 75. The member 90 is rotatably mounted on the shaft 21 and constrained from axially movement along the shaft 21 as is the carriage 75. The member 90 is forced away from carriage 75 by means of a spring 92 connected between the lower portion of the extension 85 and the upper portion of member 90. A bolt, generally designated as 94, extends slidably through the extension 85 and is threaded into the member 90 for keeping the spring 92 in axially alignment. It will be noted that when the carriage 75 is forced in counterclockwise rotation about the shaft 21, the member 90 will also be caused to rotate counterclockwise about the shaft 21 until it engages the foot 46 extending from the key-bearing carriage 22. At this time, the member 90 will stop rotating and the carriage 75 will continue to rotate against the additional contraction of the spring 92. Bolt 94 will then protrude through the top of the carriage 75 (see FIG. 4).

Referring now to FIGS. 5 and 6, the function of micrometer 80 will be explained. As noted above, the micrometer 80 is threaded through the finger carriage 75 with the pin 82 of micrometer 80 protruding below the carriage 75 and normally resting on the top surface of block 83. The block 83, defining a generally horizontal upper surface 83a and a convex lower surface 83b, is pivotally connected, indicated by reference numeral 83c, to the front wall of a housing 96a depending from the lower surface of the top of frame 10.

The crank handle 21b extends slidably through the front and back walls of the housing 960 which provide bearing surfaces preventing lateral movement of the crank 21b. A plane 97 is threaded on the crank 21b and has an upper slanted surface 97a on which the curved surface 83b of block or ca-m =83 rests (FIG. 5). A coil spring 98 is arranged concentric with the crank 21b and between the inner surface of the front wall of housing 96a and the front surface of the plane 97 thereby urging crank 21b rearwardly. The crank 21b is prevented from rearward axial movement by a nut 99 threaded thereon and abutting the front surface of the forward wall of housing 96a. As the crank 21b is rotated, the plane 97 is translated either forwardly or rearwardly depending on the direction of rotation of the crank, thereby rotating the cam 83 about its pivotal connection 830 to raise or lower the surface 83a upon which the pin 82 rests.

Still referring to FIG. 5, it can be seen that the operating lever 21a extends rearward and is connected to a transverse, rotatable bar 101 journaled with the housing 9611 at one end, indicated by numeral 102 and within a side wall of the frame 10, as at 103 at its other end. A spring 104 is tensioned between the front wall of the frame 10, as at 105 and a tab 106 depending from the rotatable bar 101 thereby causing a bias on lever 21a to urge it upwardly in its normal position.

Also rigidly connected to rod 101 in a position generally parallel to the under surface of the top of frame 10, is an extension 108. A vertical link 110 (see FIG. 2) is pivotally connected between the free end of extension 108 and the lower surface of the finger carriage 75, as at 111. When the lever 21a is depressed against the action of spring 104- the rod 101 is rotated thereby exerting a downward force on the finger carriage 75 through exextsion 108 and link 111 to cause it to rotate counterclockwise (FIGS. 3 and 4) about shaft 21. It will be noted that this motion causes the tip of finger 86 to engage the tumblers 69 protruding from lock cylinder 60 and exert a downward force on member 42 of the keybearing carriage 22 to which the lock cylinder 60 is secured, as explained above.

Operation to cut first key When it is desired to cut an original key (or a first key, as it is sometimes called) the lock cylinder or plug is removed from the lock housing and inserted in re ceptacle 42a as shown in FIG. 4. A blank key is then inserted in the lock cylinder keyhole to force the pins 69 to protrude above the exterior surface of the plug. The plug is forced up against the protrusion 59 to secure it within the hollow 54 of receptacle 42a. The entire key bearing carriage assembly 22 including the member 42 is then moved tothe left until the blank key inserted in the plug is forced against the stop member 70. The key to be cut is then inserted into the left vise 28 on the platform 24 such that it abuts the stop surface 71 integral with platform 10. This insures proper longitudinal orientation of the two keys-the one with respect to the finger 86, and the key to be cut with respect to the cutter wheel 20. When the finger 86 is located directly over a tumbler protruding from the lock cylinder, the cutting wheel 20 is located in its proper longitudinal relation with respect to the key to be cut for cutting a ward for the protruding tumbler. The key-bearing carriage assembly 22 is then moved to the right so that the finger 86 is positioned over the lock cylinder. The operating lever 21a is depressed to pull the pin carriage 75 down and force the finger '86 against the surface of the lock cylinder. It is important that the finger 86 actually engage the cylinder surface and not one of the protruding tumblers (the blank key may have to be removed for some locks) during this set up procedure. At this time, rotation of the key-bearing carriage 22 should be short of the point at which the cutting wheel 20 does any cutting. The micrometer is then at an arbitrary position and the crank handle 21b is rotated to cause the cam 83 to be lowered thereby allowing additional rotation of the pin carriage '75 and key-bearing carriage 22 (since the lever 21a is depressed) until the surface of the key to be cut just barely misses engagement with cutting .wheel 20. This is hereinafter referred to as the set up procedure, and it will be obvious that after placement of the keys, the only adjustment is the simple one of rotating the crank handle 21b while depressing the lever 21a.

The wards in the key clamped in the vise 28 are then cut to the correct depth by locating the finger 86 (after replacing the blank key if it had been removed from the lock cylinder) directly over one of the protruding tumblers and again depressing the operating lever 21 thereby rotating the pin carriage 75 and the key-bearing carriage 22 and moving the key into cutter wheel 20 by the same increment which defines the extension of the tumbler beyond the lock cylinder surface. In other words, the set up procedure allows the key which is being cut to move adjacent the cutter wheel when the operating lever is depressed and the finger engages the lock cylinder. Anything thereafter inserted between the finger and the surface of the lock cylinder will cause the key to be cut by the separation between the two when the operating lever is depressed. In my preferred embodiment, the key-bearing carriage is designed so that the radial distance from the center of its rotation (i.e., the center of the shaft about which it rotates) to the point at which the finger engages the lock cylinder is the same as the radial distance between its center of rotation and the point where the key which is to be cut engages the cutter wheel. This insures that a given angular displacement of the lock cylinder will be transmitted as the same angular displacement of the key being cut.

The structure which has thus been described will therefore cut a first key even through there is no original key available merely by inserting a blank key into the keyhole of the lock cylinder to force the tumblers to protrude beyond the external surface of the lock cylinder and subsequently forcing a key into the cutter wheel by a corresponding distance.

It is noted that the crank handle 21b and its associated adjusting means is readily adapted to accommodate keys of varying widths, whereas the micrometer 80 and its adjustable pin are suited to finer, more accurate settings which may be predetermined.

Certain advantages in this operation will be noted over prior machines. First, one simple adjustment is made after the keys are in place. Secondly, provision is made for a proper longitudinal alignment of the two keys so that the matching profiles will be properly placed relative to the key stops. Also, the particular arrangement of having a direct connection between the housing which contains the finger itself and through the tumblers engaging the blank key back through the key-bearing carriage into the key being cut establishes a direct physical linkage so that a very accurate cut is obtained with a very simple downward movement of an operating lever as described.

The next important and novel feature of the present machine is a provision wherein the proper fiat may be cut on the ward of a key once the proper depth has been established as described above. Heretofore, the fiat-cutting operation required a change of cutter wheel or it was laboriously done by hand filing on an individual basis, despite that each manufacturer provides this information for each lock model.

The flat-cutting operation of the illustrated machine is accomplished by horizontal movement of the cutter wheel 20 and its associated driven shaft 18. Referring to FIG. 2, a collar 108 is rotatably mounted on the shaft 18. A second collar 109 is mounted on the shaft 18 adjacent the collar 108, but the collar 109 rotates with the shaft 18.

A coil spring 110 is concentric with the shaft 18 and engages the collar 109 at one end and the side of the housing of the shaft 18 at the other end, as at 112. This forces the shaft 18 and cutter wheel 20 axially away from the pulley 16. This axial motion is limited by a washer 114 mounted on the shaft 18 and bearing against the outside of the housing of the cutter wheel shaft 18.

Pivotally mounted on the housing of the cutter wheel shaft is a bell crank generally designated as 118. The bell crank 118 comprises a pivotal connection as at 120 and a short arm 119 which fits into a recess in the collar 108. The second arm of the bell crank 118 is an elongated arm 124 which extends generally in the direction of the shaft 18 but is upwardly disposed therefrom. A link 125 is pivotally connected to the free end of the bell crank arm 124 and extends down to a pivotal connection intermediate of the fiat-control level 210, designated as 130a. The working end of lever 210 extends out of the front of the frame 10 of the cutting machine; and its interior end is connected to a rotatable, transverse rod 130 as at 131 (FIG. The rod 130 is journaled at one end within the frame 10, as at 133, and the other end with the housing 96a mounted below the frame (FIG. 5). The rotatable rod 130 is seen to be collinear with the rod 101, but need not be.

In operation, when the key being cut is properly aligned with the cutter wheel 20 after the lock cylinder is secured (with a blank key inserted) into the receptacle 42a, and the set up procedure, as outlined above, has been carried out, the operating lever 21a is depressed thereby rotating the finger carriage 75 counterclockwise and engaging the protruding tumblers with the finger 86 to rotate the keybearing carriage 22. It will be noted that at the same time, the drift control feature has been rendered operative since the member 90 is forced down upon the foot 46 thereby pressing it against the frame 10. The key-bearing carriage is prevented from axial motion at this time due to the ring bearings 48 and 50 which are integral with the foot 46 and adjacent the cylinder bearing 22a of the carriage 22 on either side.

When the fiat-control lever 210 is then depressed, the link 125 is also moved downward pivoting the bell crank 118 along the axis of the cutter wheel shaft 18 against the collar 109 thereby compressing the spring 110. This motion, as seen by the direction of the arrows in FIG. 2, forces the cutter wheel 20 to move transverse to its vertical plane for cutting a flat in the key which is tightly held when the operating lever 210 is held down. This horizontal motion of cutter wheel 20 is illustrated in FIG. 2 by the dotted cutter wheel as shown.

Motion of the cutter wheel 20 axially of its shaft 18 is limited, as seen in FIG. 2, by a ring integral with collar 108 and fitting into an annular recess provided in a horizontal micrometer, generally designated in FIG. 1 as 140. The micrometer comprises a stationary threaded portion 141 which has a flattened head 143 mounted in the vertical wall of the shaft housing adjacent the cutter wheel. A moveable portion 140a of the micrometer 140 is threaded on the stationary portion 141. A thumb wheel 144 is fixed to the moveable portion 140a and has been roughened for easy finger manipulation. It provides a simple control for the moveable portion 140a allowing motion along a line parallel to the shaft 18 of the cutter wheel 20 by rotation of the thumb wheel 144.

At the end of the moveable portion 140a is the recess in which fits the ring 115 of the collar 108. Hence, once the micrometer 140 has been moved to a particular setting by rotation of thumb wheel 144 which indicates the limit of the axial motion of the cutter wheel 20, the ring 115 of collar 108 will bear against a stopper portion 146 of the recess in the moveable portion 140a to limit the axial motion of the shaft 18. This simple hand setting, which faces the operator and is easily readable by means of a scale 149 fixed on the thumb wheel 144 of the micrometer 140, provides an easy and accurate means for setting the predetermined width of the flat of the key according to the manufacturers specification without the need for changing the cutter wheel.

The flat-control provision is considered to be an important feature of the present invention because it allows an operator to not only cut flats in the general household type look, but it also allows one to cut the different widths required in the fiat steel key by a simple setting. A slotter wheel 20 for cutting wards in flat steel key 150 is shown in FIG. 8.

An example will be given to illustrate the cutting of proper flats in a fiat steel key. Suppose the flat required is 0.080 inch and a 0.035 inch slotter wheel is used. A first cut with the 0.035 inch slotter is made as described above, and the key is withdrawn from the cutter by releasing the operating control lever 21a. Thumb wheel 144 is adjusted to read 0.045. Lever 210 is depressed. A second cut is then made so that the total width of the flat is 0.080 inch (leaving a 0.010 inch sliver to be nudged off) without having changed the slotter wheel.

As mentioned above, when the machine is being used to cut a first key, the particular setting on the micrometer 80 is not important since its only function is to serve as a stop in setting up the key-cutting operation such that the key to be cut, when clamped in the left vise 28 of the keybearing carriage 22, will barely touch the rotating cutter wheel 20. However, I have found that the utility of the machine can he significantly increased by means of micrometer 80 for cutting keys without the need of even a lock cylinder and tumblers. When used in this manner, I refer to the machine as a code machine since the key is cut to specifications supplied by the manufacturer and the code numbers on the lock. In practice, the lock cylinder is usually removed from its housing in order to get the code of the ward depths required to open the lock.

In cutting a key to fit a lock by code, the lock model is first noted to determine how many wards are required and what their longitudinal spacing is along the edge of the key. The lock is then examined to obtain the code, which, for example, may be 1-4-2-5 which represent the respective depths of four wards proceeding from the collar to the tip of the key. The manufacturers specifications are then again consulted to translate the code numbers into dimensions. Let us assume that each increment of code number is indicated as representative of 0.015 inch; hence, the code represents ward depths respectively of 0.015 inch, 0.060 inch, 0.030 inch, and 0.075 inch.

These ward depths are then cut into the key with the proper longitudinal spacing which is facilitated by a code plug which I have developed and which will now be described in more detail.

The code plug is shown in FIG. 7. It is a cylindrical plug preferably made of some metal and it contains information of the longitudinal spacing of wards for a particular manufacturers lock model. As seen from FIG. 9 the external surface of the plug is divided by lines, as at 170 and 171, parallel to its axis and having equal spacing about a circumference of the plug thereby defining external lengthwise segments of the plug on which the manufacturers model number may be identified. As shown, at the lefthand portion of a particular coding line, the manufacturer and model are designated. Arranged in axial alignment therewith and, hence, identified with a particular manufacturer and lock model, are a series of dents or notches shown generally as 172. The notches 172 indicate the longitudinal spacing of the wards which are to be cut in the key. Hence, in my particular machine when the finger 86 lines up with one of the notches 17 in the code plug, the cutter wheel 20 is properly aligned with a key being cut and clamped in the left vise 28. For use as a code machine, the set up procedure is slightly modified, the micrometer 80 is set to zero and the key being cut is inserted in the left vise 28 with the code plug inserted in the receptical 54. The stops are used as before to get proper longitudinal alignment. The rotatable crank 21b is then adjusted to move cam 83, as above-described, to a position such that the blank key barely touches the surface of the cutter wheel 20 when the operating lever 21a is depressed. Lever 21a is released and a setting is registered on the micrometer 80 which is calibrated in thousandths of an inch, as shown, to retract the micrometer pin 82 to allow further rotation of the finger carriage 75 and key-bearing carriage 22. If pin 82 of the micrometer 80 is raised by a distance of 0.025 inch, reading the micrometer scale, a corresponding ward depth will then be cut in the key when operating lever 21a is again depressed.

It will be noted that the finger 86 in this case engages one of the notches in the code plug. Also as above-described, manufacturers specifications on flats may be cut at this time. It can therefore be seen that given the manufacturers specification for ward depth and spacing, the present machine can be easily used to cut an original key once the coding information from the lock has been obtained.

However, as already shown, we have found it particularly useful to use the type of code plug which was described and shown in FIG. 9 to permanently record the ward spacing for a plurality of lock models according to manufacturer and lock type. A number of such plugs can be used and facilitate permanent recording of many commonly used lock models.

It will be noted that a master key system of the split pin type could easily be implemented on a set of locks of like model by selecting one or more wards, noting their depths in individual keys and including a split pin or tumbler combination with the outermost pin being, for example, 0.050 inch. The master key is cut with a ward depth of an additional 0.050 inch using micrometer 80, as described. Use of the fiat-control lever 210 will obviate the need for individual filing I have found out.

It will also be obvious to those skilled in the art that keys may be cut with my machine from direct measurements by using the micrometer 80 to duplicate ward depths.

Having thus described my machine and its operation either as a duplicating machine, a first key machine, a code machine, or a machine for implementing master lock systems, it will be obvious that certain modifications made or equivalent structures substituted for those which I have illustrated without changing the operation of or results produced by my machine. It is intended that such modifications be covered and that my invention be limited only by the appended claims.

What is claimed is:

1. A machine having a rotating cutting wheel for cutting wards in a key being cut equal depth to the protrusion of tumblers beyond the surface of a lock cylinder when containing a blank key comprising:

a first carriage rotatable about a shaft parallel to the axis of rotation of said cutter wheel including a holder for the key being cut adjacent said cutter wheel and a receptacle for securing said lock cylinder, said carriage also being moveable axially of said shaft;

a second carriage rotatable independently of said first carriage and constrained against motion transverse to said rotational motion including a component disposed adjacent said receptacle of said first carriage for engaging said lock cylinder secured therein and lever means attache-d to said second carriage for rotating it in a direction such that said component engages said lock cylinder thereby rotating said first carriage and moving said key being cut into said cutter wheel; and

adjustable means for limiting the rotation of said carriages;

whereby when said first carriage has been moved axially of said cutter wheel to align said component of said second carriage with a tumbler forced to protrude beyond the surface of said lock cylinder by an inserted blank key and said lever means is operated to rotate said carriages, said component will engage said tumbler and move said key being cut into said cutter wheel by an amount equal to the extension of said tumbler beyond the surface of said cylinder.

2. The machine of claim 1 wherein said adjustable limiting means comprises:

a bolt threadably mounted on said second carriage in the direction of rotation thereof;

scale means associated with said bolt for recording the axial displacement thereof relative to said second carriage; and

adjustable stopper means for abutting said bolt when said second carriage is rotated by said lever means to stop the motion thereof.

3. The machine of claim 1 further comprising:

drift control means limiting axial motion of said first carriage in response to the operation of said lever means; and

means for moving said cutter wheel along its axis of rotation for cutting flats in said key being cut.

4. The machine of claim 3 wherein said fiat cutting means comprises:

a driven shaft extended in the direction of the axis of rotation of said first carriage;

mounting means for securing said cutter wheel on said driven shaft;

spring means urging said shaft in axial motion;

a fiange on said driven shaft for limiting the displacement of said shaft in the direction of urge by said spring;

lever means coupled to said shaft including a rotatable collar on said shaft for moving said shaft axially against the force of said spring means; and

presetable stop means engaging said collar for limiting the axial motion of said shaft by said lever means.

5. A key-cutting machine comprising:

moveable means for holding a key adjacent a rotating cutter wheel, said means being moveable in the plane of rotation of said cutter wheel and transverse thereto;

sensing means including a finger for determining the displacement of tumblers beyond the surface of a lock cylinder in which a blank key is inserted and for displacing said finger relative to a reference by a distance representative of said sensed tumbler displacement;

means responsive to said sensing means for forcing said holding means in the direction of said cutter wheel to cut a ward in said key of a depth equal to said finger displacement; and

means associated with said sensing means for changing the displacement of said finger by a predetermined amount.

6. The apparatus of claim further comprising:

means responsive to said forcing means for preventing motion of said holding means in a direction transverse to the rotation of said cutter wheel when said key is being cut; and

means coupled to said cutter wheel for translatingjt along its axis of rotation to cut a fiat in the key being cut.

7. The machine of claim 5 wherein said means associated with said sensing means further defines micrometer means including a bolt threaded thereon for adjusting said finger displacement by a predetermined amount independently of said forcing means.

8. The machine of claim 5 characterized by said finger being confined to motion in a plane parallel to the plane of rotation of said cutter wheel and bearing a constant spacial relation thereto.

9. The machine of claim 5 further comprising:

a receptacle mounted on said holding means adjacent said finger of said sensing means; and

an elongated plug of constant cross section defining an axis and an exterior surface, said exterior surface of said plug bearing indicia representative of the longitudinal spacing between wards of keys of a common model whereby said plug may be moved transverse to the plane of rotation of said cutter wheel adjacent said finger thereby translating said holding means by a corresponding amount.

10. The machine of claim 5 wherein said sensing means comprises carriage means rotatable in the plane of rotation of said cuttetr wheel and said finger being confined to motion in a plane parallel thereto, said finger cooperating with said sensing means responsive to said forcing means to move said holding means in the direction of said cutter wheel to cut a ward in said key of a depth equal to said finger displacement, said machine further comprising means for establishing a reference relative to the key being cut and the key inserted in said lock cylinder such that said cutter wheel assumes the same position longitudinally of said key being cut as said finger assumes longitudinally of said inserted key.

11. A method of cutting a key for a lock from instructions comprising: locking a member defining a reference surface in a key cutting machine, said machine provided with calibrated measuring means for setting the desired depth of a cut, said reference surface providing a reference for depth of cut and spaced indicia for providing information for the lateral spacing of wards in the key to be cut; aligning said key to be cut with a cutter wheel on said machine for proper ward placement; engaging said reference surface with indicator mcans on said machine to bring said key adjacent to said cutter wheel without cutting the key; then setting said measuring means to a predetermined value representative of the desired depth of the ward at which the machine is set; and cutting said key at said ward location to said preset depth.

References Cited UNITED STATES PATENTS 2,757,578 8/1956 Saucedo -l3.05 3,118,346 l/1964 Simon 90l3.05 1,254,442 1/ 1918 Smith 90-l3.05 1,895,849 1/1933 Haubroe 90-1305 GERALD A. DOST, Primary Examiner.

US. Cl. X.R. 90-13.05 

